Generics - General Questions

What is the output of the following program?

public class Main {
    static <T extends Comparable<T>> T max(T a, T b) { return a.compareTo(b) >= 0 ? a : b; }
    public static void main(String[] args) {
        System.out.println(max(4, 9) + " " + max("kiwi", "apple"));
    }
}

What is type erasure?

Which wildcard allows adding Integer values to the list?

What is the output of the following program?

public class Main {
    static class Box<T> { T v; Box(T v) { this.v = v; } T get() { return v; } }
    public static void main(String[] args) {
        Box<Integer> b = new Box<>(41);
        System.out.println(b.get() + 1);
    }
}

What is the output of the following program?

public class Main {
    public static void main(String[] args) {
        java.util.List<Integer> nums = java.util.List.of(1, 2, 3);
        int s = 0;
        for (int n : nums) s += n;
        System.out.println(s);
    }
}